Thule

Thule, the name generally given by the ancients to the most northerly part of Europe known to them, of which their want of knowledge was eked out by the imagination. According to Pliny it was an island in the northern ocean, discovered by the navigator Pytheas of Massilia, who reached it after six days' sail from the Orcades. Most probably Pytheas followed closely the eastern coast of Great Britain, and heard exaggerated reports of the groups of islands farther north—the Orkneys and Shetlands, perhaps even Iceland—which he thought lay close to the Arctic Circle. The usual Roman phrase was Ultima Thule.